Method for delivering a device to a target location

ABSTRACT

Capsule ( 60 ) moves through the gastrointestinal tract ( 62 ) in a first pass to generate a map of the gastrointestinal tract, and to identify a location of interest. In its second pass, capsule ( 60 ) moves through the gastrointestinal tract, and is controlled to perform a job at the identified location. Repeated localizations generate generate a map of the route taken by the capsule in the gastrointestinal tract ( 62 ). images displayed on the image monitor ( 61 ) are compared with the generated map displayed on the position monitor ( 63 ) to identify the location of a pathology ( 72 ).

PRIOR APPLICATION INFORMATION

The present application claims benefit from the InternationalApplication Number PCT/IL99/00554 filed 21 Oct. 1999 and entitled “AMETHOD FOR DELIVERING A DEVICE TO TARGET LOCATION”, which in turn claimspriority from Israeli Application 12727, filed on 22 Oct. 1998.

FIELD OF THE INVENTION

The present invention relates to a method for identifying a targetlocation in the gastrointestinal tract and for direct delivery of adevice to the identified location.

BACKGROUND OF THE INVENTION

In the gastrointestinal tract, the stomach is connected, through thesmall intestine, a long tube that folds many times to fit inside theabdomen, to the large intestine. There are numerous pathologies of thegastrointestinal tract, such as lesions causing chronic gastrointestinaltract blood loss, which occurs in about 2% of US adults, malignancies,most of which give a poor prognosis, and bowel obstructions; simple,closed-loop, strangulated and incarcerated. Some of these pathologies,such as small intestinal tumors, are difficult to diagnose. Diagnosticmethods of the small intestine are usually symptom related or invasive,such as barium enemas or surgery. New methods of diagnosis can lead toan earlier diagnosis and improved prognosis.

U.S. Pat. No. 5,604,531 describes an in vivo video camera system whichcan image the gastrointestinal tract. Reference is now made to FIG. 1,which is a block diagram illustration of a prior art in vivo videocamera system for imaging the gastrointestinal tract. The in vivo videocamera system typically comprises a swallowable capsule 10 for viewinginside the digestive system and for transmitting video data, a receptionsystem 12 typically located outside a patient, and a data processor 14for processing the video data. The data processor 14 typically operatestwo monitors, a position monitor 16 on which the current location of thecapsule 10 within the digestive system is displayed and an image monitor18 on which the image currently viewed by the capsule 10 is displayed.

The reception system 12 can either be portable, in which case, the datait receives is temporarily stored in a storage unit 19, prior to itsprocessing in data processor 14, or it can be stationary and close tothe data processor 14.

Reference is now made to FIGS. 2 and 3 which are a schematicillustration of calculations performed by a prior art data processor forprocessing the video data obtained by the above in vivo video camerasystem. FIG. 2 is a front view illustration of the patient 22 with anantenna array 30 wrapped around him. On it, four antennas 34 a–34 d arenoted. Antennas 34 a and 34 b are located in a column at one side of thepatient 22 and antennas 34 c and 34 d are located in a column at theother side of the patient 22.

Since the strength of a signal received by any given antenna depends onits distance from and angle to the transmitter, the ratio of the signalstrengths between any two antennas, which have the transmitter betweenthem, is constant along a curve which intersects the location of thetransmitter. Thus, antennas 34 a and 34 b define curve 30 a and antennas34 c and 34 d define curve 30 b.

The intersection of curves 30 a and 30 b is the location of thetransmitter which is the location of the capsule 10. The curves 30 a and30 b are typically determined in a calibration step for a pre definednumber of constant values.

The designation of antennas 34 a–34 d depends on and is determined fromthe width L₁ of the patient 22, which value is typically provided todata processor 14 (of FIG. 1). Alternatively, there can be a pluralityof antenna arrays 30, one for each of a pre-defined number of widths L₁.The antennas 34 a–34 d are then constant for each antenna array 30.

The location of the capsule 10, thus generated, is typically denoted bya two-dimensional vector P, having a length P and an angle □, from thecenter point O of an X-Y coordinate system.

The cross-sectional location (within an X-Z plane) of the capsule 10 canalso be determined using a similar calculation to that illustrated inFIG. 2. A cross-section of the patient 22 is illustrated in FIG. 3. Forthis determination, four antennas 34 e–34 h, which are opposite in across-sectional manner, are utilized.

Once again, the ratio of the signal strengths between two antennas,which have the transmitter between them, is constant along a curve whichintersects the location of the transmitter. Thus, antennas 34 e and 34 hdefine curve 30 c and antennas 34 f and 34 g define curve 30 d.

The location of the capsule 10 thus generated is typically denoted by atwo-dimensional vector Q having a length Q and an angle □, from thecenter point O.

The two vectors P and Q are combined to determine the three-dimensionallocation of the capsule 10. The location can be displayed two- orthree-dimensionally on position monitor 16 (of FIG. 1), typically,though not necessarily, as an overlay to a drawing of the digestivetract.

There exist methods for the delivery of medicament to a selected site inthe gastrointestinal tract, such as the use of time delivery capsulesmade of material that dissolves in a particular environment and/orwithin a particular time period, within the gastrointestinal tract. Inthese methods, the delivery of medicament is dependent on thepredictability of the particular environment to which the capsule isdirected.

Controllable apparatuses for delivery of medicaments are described inU.S. Pat. Nos. 5,558,640 and 4,239,040. While using these apparatuses orcapsules the delivery of medicament may be obstructed, such as by foldsin the intestine.

These methods can not be relied upon for localized release of amedicament.

U.S. Pat. No. 5,279,607 describes a method of obtaining directional datafrom the passage of an ingestible radio signal transmitting capsule.This data is subsequently compared to directional data from a capsulecarrying medicament passing through the alimentary canal, for remotelytriggering the release of medicament at a calculated geometric locationalong the gastrointestinal tract. A location selected in this method,cannot be aligned with sites of interest, such as pathologies, since nodiagnostic information, such as information relating to the pathology,can be obtained in this method. Furthermore, due to the constantperistaltic movement of the alimentary canal, the geometric location ofa site is not the same in a first and second pass, so that this oneparameter is only partially sufficient for selection of a site.

There exist no medicament delivering systems which combine diagnosticand therapeutic processes.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a method fordelivering a utility device to a target location in the gastrointestinaltract. The method combines identification of a target in thegastrointestinal tract and delivery of a utility device to theidentified target location. The method of the present inventioncomprises the steps of:

-   -   a) generating a map of the gastrointestinal tract, employing a        sensing and utility device for a first pass, or, optionally, a        plurality of passes through the gastrointestinal tract; and    -   b) delivering the sensing and utility device to a target        location identified on the map, using the sensing and utility        device in a second pass or, optionally, a plurality of passes,        through the gastrointestinal tract. The sensing and utility        device used in the second pass, may be the same or different        than the device used in the first pass.

The term “sensing and utility device”, in the present invention, refersto a device which is swallowable or placeable (such as described in ILpatent application number 122716, assigned to the common assignees ofthe present invention and which is hereby incorporated by reference),and is capable of sensing selected parameters of the gastrointestinaltract. The device also comprises means for performing a job in thegastrointestinal tract. It is controllable and is capable of beingmonitored and of generating a map of the gastrointestinal tract.

The sensing and utility device may comprise, for example, any one or anycombination of a video camera, which generates an image of thegastrointestinal tract, or sensing means, such as temperature, pressureor pH sensors or means for sensing the presence of blood,microorganisms, parasites or pathological indications or any objectsalien to the gastrointestinal tract.

Means for performing a job may be any means suitable for researching,diagnosing or treating pathologies in the gastrointestinal tract, forexample, fluid or cell sampling means, marker releasing means ormedicament releasing means.

A map of the gastrointestinal tract may be generated by inserting thesensing and utility device into the gastrointestinal tract, monitoringthe progress of the device through the gastrointestinal tract andoptionally displaying the locations, two or three dimensionally, on aposition monitor.

Monitoring the device is by periodically or repeatedly locating thedevice, preferably, as described in U.S. Pat. No. 5,604,531 assigned tothe common assignees of the present invention. U.S. Pat. No. 5,604,531is hereby incorporated by reference.

Delivering the sensing and utility device to a target locationidentified on the map comprises the steps of inserting the sensing andutility device into the gastrointestinal tract, in a second pass,receiving data from the device, either visual, from a video camera, orfrom the output of other sensing means, performing signal analysis ofthe data generated in the first pass and the data received from saidsensing and utility device in the second pass; and controlling, such asby IR or telephony, the sensing and utility device according to thesignal analysis.

The method of the present invention may be used for research, diagnosticor therapeutic purposes in the gastrointestinal tract.

BRIEF DESCRIPTION OF THE FIGURES

The present invention will be understood and appreciated more fully fromthe following detailed description taken in conjunction with thedrawings in which:

FIG. 1 is a block diagram illustration of a prior art in vivo videocamera system for imaging the gastrointestinal tract;

FIGS. 2 and 3 are schematic illustrations of calculations performed by aprior art data processor for processing the video data obtained by thein vivo video camera system for imaging the gastrointestinal tract,utilizing an antenna array, wherein FIG. 3 is a top view illustration ofthe antenna array and FIG. 2 is a cross-sectional illustration of theantenna array.

FIG. 4 is an illustration of a sensing and utility device according to apreferred embodiment of the invention;

FIG. 5A is an illustration of a storage compartment, according to apreferred embodiment of the invention, in a recoiled-position of the bistable spring;

FIG. 5B is an illustration of a storage compartment, according to apreferred embodiment of the invention, in an extended position of the bistable spring;

FIG. 5C is an enalrgement of the storgae compartment tip, according to apreferred embodiment of the invention;

FIG. 6 is an illustration of a sensing and utility device operableaccording to a preferred embodiment of the invention; and

FIG. 7 is an illustration of a generated and displayed map in the methodaccording to a preferred embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The method of the present invention combines diagnostic and therapeuticprocesses. For example, the method combines identifying and localizing apathology in the gastrointestinal tract with administrating treatment tothe location of the pathology, by non invasive means. This combinationis provided by employing a sensing and utility device which is insertedinto the gastrointestinal tract, either by swallowing it or by placingit in the gastrointestinal tract. The above mentioned IL patentapplication 122716 describes a device for the placement of an autonomouscapsule in the gastrointestinal tract, which bypasses the need forswallowing the capsule by the patient.

Reference is now made to FIG. 4 which is an illustration of a sensingand utility device according to a preferred embodiment of the invention.The sensing and utility capsule shaped device, generally referenced 40,typically comprises a light source 42, a viewing window 44, throughwhich the light illuminates the inner portions of the digestive system,a camera system 46, such as a charge-coupled device (CCD) or CMOScamera, which detects the images, an optical system 48 (typicallycomprising a mirror 47 and a focusing lens 47′) which focuses the imagesonto the CCD or CMOS camera system 46, a transmitter 41, which transmitsthe video signal of the CCD or CMOS camera system 46, a power source 43,such as a battery, which provides power to the entirety of electricalelements of the capsule and a storage compartment 45, for thecontrollable discharge of medicaments or markers or for the controllablecollection of fluid or cell samples from the environment, such as in abiopsy procedure.

The sensing and utility device can additionally include any known sensorelement 49 such as temperature, pressure or pH sensors or means forsensing the presence of blood, microorganisms, parasites or pathologicalindications or any objects alien to the gastrointestinal tract.

Reference is now made to FIGS. 5A, 5B and 5C which are illustrations ofa storage compartment, according to a preferred embodiment of theinvention.

Storage compartment 55 is located preferably at an end of the sensingand utility device, generally referenced 50. The storage compartment isdefined by an inflexible barrier 59 and the device shell. The storagecompartment contains a pouch 56 made of flexible material which isencased by the device outer shell 52 and by a firm diaphragm 54 havingan elasticity which will allow it to accommodate to a capsule shape.Diaphragm 54 is horizontally movable between the inflexible barrier 59and the device tip. At the device tip there is an area 58, in the outershell of the device, which is permeable and which allows passage ofsubstances from or into the pouch 56. Permeability may be conferred, forinstance by the area 58 being porous or sieve like. The pouch 56 isdesigned to retain substances such as releasable medicaments or markersor such as fluid or cell samples from the gastrointestinal tractenvironment. The pouch 56 bulk is determined by a bi stable spring 53,preferably made of a memory shape metal such as TiNi. The spring 53 isattached, at one end to the solid barrier 59, and at its other end, tothe diaphragm 54. The spring 53 may be made to extend (as shown in FIG.5B) or recoil (as shown in FIG. 5A) by providing different temperatures,as known in the art (the means for providing different temperatures,such as conducting wires, are not shown). Thus, the pouch 56 bulk may bereversably increased or decreased.

FIG. 5A illustrates a piercing pin 57 which is attached to the pouchwall and which protrudes into the pouch 56 inner space, in the directionof the opposing pouch wall 56′. For releasing a substance from pouch 56into the gastroinestinal tract environment, spring 53 is made to extend,causing diaphragm 54 to move towards the device end, thrusting thepeircing pin 57 into the opposing pouch wall 56′, rupturing it. Asubstance contained in the pouch 56 will be released into a space 51provided between the opposing pouch wall 56′ and the outer shellpermeable area 58. The released substance may then pass through theopenings in the permeable area 58 into the gastrointestinal tract.

FIG. 5B illustrates a pouch 56 meant for collecting a sample from thegastrointestinal tract. In this embodiment the bi stable spring 53 islodged in opposing pouch wall 56′. The spring 53 is made to recoil,pulling with it diaphragm 54 and piercing pin 57, such that piercing pin57 is dislodged from the opposing pouch wall 56′, rupturing it andleaving an opening in the pouch, through which substances from theenvironment are drawn into the pouch 56. The opening in the pouch issealed after the sample is drawn in from the environment, ensuring afixed volume and sterility of the collected sample.

Pin 57 may be a hollow cylinder through which substances may pass to orfrom the gastrointestinal tract.

FIG. 5C is an enlargement of the device end, through which substancesare drawn into, or released from, the pouch. As can be seen in thisfigure, space 51 is provided, ensuring that the pin 57, either beforebeing dislodged from wall 56′ for collecting substances, or whenpiercing wall 56′ for release of substances, doesn't protrude furtherthan the device shell 52 and injure the patient's insides.

Reference is now made to FIGS. 6 and 7. FIG. 6 is an illustration of asensing and utility device operable according to a preferred embodimentof the invention, and FIG. 7 is an illustration of a map of thegastrointestinal tract generated in the method, according to a preferredembodiment of the invention.

Capsule 60 moves through the gastrointestinal tract 62 in a first passto generate, by visual means, a map of the gastrointestinal tract and toidentify, by visual means or other sensor means, a location of interestin the gastrointestinal tract. In its second pass, capsule 60 movesthrough the gastrointestinal tract and is controlled to perform a job atthe identified location.

Recognition of the location, identified in the first pass, is done inanalyzing unit 65, by analysis of the map generated in the first passand bringing into conformity parameters, visual or others, obtained inthe first pass and in the second pass. This may be acheived by any ofthe well known techniques of image matching by correlation, as done inimage analysis, or any other suitable signal analysis techniques.

As the capsule 60 moves through the digestive system (gastrointestinaltract) 62, in its first pass, it views the walls of the digestive systemin the method described in FIGS. 2 and 3 and in U.S. Pat. No. 5,604,531,and transmits the resultant images to a reception system 64 typicallylocated outside a patient. The reception system 64 receives amultiplicity of versions of the images, each version received by adifferent antenna (described in FIGS. 2 and 3) and either stores thereceived signals in the storage unit 68 or provides the receivedsignals, directly, by IR or telephony, to the data processor 66. Thedata processor 66 typically operates two monitors, a position monitor63, on which the current location of the capsule 60 within the digestivesystem is recorded, and, optionally, displayed and an image monitor 61,on which the image currently viewed by the capsule 60 is displayed.

The reception system 64 can either be portable, in which case, the datait receives is temporarily stored in a storage unit 68 prior to itsprocessing in data processor 66, or it can be stationary and close tothe data processor 66.

The capsule 60 location can be displayed two- or three-dimensionally onposition monitor 63, typically, though not necessarily, as an overlay toa drawing of the digestive tract. The progress of capsule 60 ismonitored by repeated or periodic localization of the capsule, and canbe displayed on position monitor 63.

A forward filming device can be distinguished from a backwards filmingdevice by the flow direction of the image. Information relating to thedirection of the device motion enables more precise localization of thestorage compartment end of the device. Furthermore, analysis of theoptical flow enables to calculate the device velocity in thegastrointestinal tract.

The repeated localizations generate a map of the route taken by thecapsule in the gastrointestinal tract 62. The generated map 70 is shownin FIG. 7. For maximum accuracy, images displayed on image monitor 61are compared with the generated map 70 displayed on position monitor 63to identify the location of a pathology 72, though, a location may beidentified by analysis of parameters other than visual (such as pH,temp, etc.), which were sensed during the first pass in thegastrointestinal tract.

Upon identifying the location of a pathology 72 on the gastrointestinaltract map 70, either visually or by analysis of other sensor meansinput, capsule 60 is inserted into the gastrointestinal tract for asecond pass. As capsule 60 moves through the digestive system 62, in itssecond pass, it is monitored as above. When arriving at the location ofthe pathology 72, or at any other point on map 70, determined as thepoint for advantageously releasing medicament for the treatment of thepathology, the capsule 60 is controlled to release the medicament fromthe medicament storage compartment of the capsule (45 in FIG. 4). Therelease of the medicament may be autonomous, automatically controlled byanalyzing unit 65 or remotely controlled by an external operator.

It will be appreciated by persons skilled in the art that the presentinvention is not limited by what has been particularly shown anddescribed herein above. Rather the scope of the invention is defined bythe claims which follow:

1. A method comprising: recording a first set of images from agastrointestinal tract using a swallowable imaging device; identifyingan image showing a location of interest; recording a second set ofimages from the gastrointestinal tract using a swallowable imagingdevice; and performing image analysis by comparing images from the firstset with images from the second set to identify in the second set animage of interest corresponding to an image in the fist set, therebydetermining the location of the imaging device relative to the locationof interest.
 2. The method according to claim 1, wherein the imagingdevice is to generate data, and wherein the imaging device is a capsulecomprising: means for signal analysis of data generated in a first passand a second pass; and means for controlling the imaging device in asecond pass according to said signal analysis; and means for performinga job in the gastrointestinal tract.
 3. The method according to claim 1,comprising the steps of: inserting the imaging device into thegastrointestinal tract in a first pass; locating the imaging device; anddisplaying the location on a position monitor.
 4. The method accordingto claim 3, further comprising a step of displaying the location of theimaging device two or three dimensionally.
 5. The method according toclaim 4, wherein the location of the imaging device is displayed as anoverlay to a schematic presentation of the gastrointestinal tract. 6.The method according to claim 1, wherein the step of recording a firstset of images using a swallowable imaging device comprises recording thefirst set of images in a first pass, and wherein the step of recording asecond set of images using a swallowable imaging device comprises:recording the second set of images from the gastrointestinal tract in asecond pass; performing image analysis by comparing images from thefirst pass and of images from in the second pass; and determining thelocation of the imaging device relative to the location of interest. 7.The method according to claim 6, wherein the first pass and the secondpass are one or more passes.
 8. The method according to claim 1, whereinthe location of interest is a location of a pathology.